TGFB1 and neoplasm: We observed a strong enhancement of FOXP3 expression and regulatory activity of purified γδ T cells stimulated with phosphoantigen and TGF-β in the presence of Vit C. More importantly, strong hypomethylation of FOXP3 TSDRs was observed only in the presence of Vit C, suggesting that TGF-β frequently expressed in the tumor microenvironment might prime local γδ T cells for suppressive activity if additional epigenetically active signals are present.112 In some circumstances, however, it appears that γδ T cells can also downregulate αβ T cell responses independent of FOXP3 expression.